C5 Complement Test: Booking, Price, and Results
About C5 Complement Test: Booking, Price, and Results
| Field | Value |
|---|---|
| Also Known As | Complement Component 5, C5 Complement Component, C5 Antigen, C5 Functional Assay |
| Sample Type | Venous blood (serum) |
| Fasting Required | Preferred (12 hours) but not mandatory |
| Report Time | 2 to 6 days |
| Recommended For | All ages, both genders |
| Price | Starting at ₹6,400 |
What Is a C5 Complement Test?
The C5 Complement test measures the level and functional activity of the C5 protein in your blood. C5 is a key part of the immune system's complement cascade, a series of proteins that work together to fight infection and clear damaged cells. Doctors order this test when they suspect a problem with the complement system, such as repeated infections or an autoimmune condition. It is also known as the C5 Complement Functional Assay or C5 Antigen test, and it uses a serum sample drawn from a vein in the arm.
What Does a C5 Complement Test Measure?
This test can be run in two ways: as an antigen test or as a functional test. Together, they provide a complete picture of whether C5 is present in sufficient amounts and functioning properly.
The table below summarises what each component assesses:
| Component | What It Assesses |
|---|---|
| C5 Antigen | The concentration of C5 protein in the blood |
| C5 Functional Activity | Whether the C5 protein is active and able to perform its role in the immune response |
The C5 protein plays a central role in forming the membrane attack complex (MAC), a structure that destroys bacteria and other pathogens. A deficiency in either the amount or the activity of C5 can leave the body vulnerable to certain infections and immune disorders.
Why Is a C5 Complement Test Done?
A doctor may order this test when investigating immune system problems or unexplained infections.
Common Symptoms That May Require This Test
The following symptoms may prompt a doctor to investigate the complement system:
- Repeated or unusually severe bacterial infections
- Persistent fatigue without a clear cause
- Joint pain or swelling
- Skin rash, particularly one associated with immune conditions
- Unexplained fever
- Swollen lymph glands
- Abdominal pain or digestive problems
Conditions This Test Can Help Detect
This test is used to investigate a range of immune and kidney-related conditions. These include:
- C5 deficiency (inherited or acquired)
- Undetectable total complement levels found on a CH50 screening test
- Increased susceptibility to Neisseria infections, including meningitis and gonorrhoea
- Autoimmune disorders, where the immune system attacks the body's own tissues
- Paroxysmal nocturnal haemoglobinuria (PNH), a rare blood disorder causing red blood cell destruction
- Atypical haemolytic uraemic syndrome (aHUS), a rare kidney disorder
- Complement-mediated kidney diseases
C5 Complement Test for Chronic Disease Monitoring
Tracking C5 functional activity over time helps doctors understand how well a patient's complement system is responding to treatment. Some complement-mediated conditions, including certain kidney disorders, are treated with a drug called eculizumab, which works by blocking C5 activity. Monitoring C5 levels and functional activity is an important part of managing patients on this therapy.
How to Prepare and What to Expect
Preparing for this test is straightforward. The steps below will help you feel confident on the day of collection.
Do You Need to Fast?
Fasting for 12 hours before the test is preferred but not strictly required. Water is generally fine to drink. If your doctor has ordered additional tests at the same time, ask whether fasting is needed for those.
Practical Tips Before Your Test
A few simple steps will help ensure an accurate sample:
- Tell your doctor about all medications you are taking, especially eculizumab or any other C5 inhibitor drugs.
- Stay well hydrated before the test.
- Avoid strenuous physical activity on the day of the test.
- Wear a loose-fitting top with sleeves that roll up easily for the blood draw.
- Handle and store the sample correctly if opting for home collection, as temperature control is critical for this test.
Step-by-Step Procedure
Here is what to expect during sample collection:
- A trained phlebotomist cleans a small area on your arm with an antiseptic solution.
- A fine needle is inserted into a vein, usually in the crook of your elbow, to draw a small amount of blood into a collection vial.
- After collection, the sample is left to clot at room temperature for approximately one hour.
- The serum (the liquid part of the blood) is separated from the cells as soon as possible, ideally within two hours of collection.
- The serum is frozen promptly to preserve complement activity for accurate testing.
- The frozen sample is transported to the laboratory under cold-chain conditions for analysis.
Factors That Can Affect Accuracy
Several factors can affect the reliability of your C5 Complement test results:
- Improper storage or delayed freezing of the sample, which is one of the most common causes of falsely low results
- Fatty or turbid (cloudy) blood samples, which can interfere with the functional assay
- Complement consumption caused by an active infection or autoimmune flare at the time of testing
- Medications such as eculizumab, which can elevate measured C5 antigen levels
Understanding Your C5 Complement Test Results
The C5 complement test results should always be reviewed alongside your medical history and any other tests your doctor has ordered. The table below shows the general reference ranges for both components.
| Parameter | Normal Range | Unit |
|---|---|---|
| C5 Complement (Antigen) | 10.6 to 26.3 | mg/dL |
| C5 Complement (Functional) | 29 to 53 | unit/mL |
These ranges are general guidelines. Your doctor will interpret your results based on your age, health history, and other factors. Always consult a qualified healthcare professional for personalised medical advice.
What Abnormal Values May Indicate
- Low C5 levels may suggest an inherited or acquired C5 deficiency or complement consumption due to infection or autoimmune activity.
- When C5 is absent along with low C3 and C4, it may indicate overall complement system consumption.
- When only C5 is absent, an isolated C5 deficiency is more likely.
Results During Special Conditions
Patients receiving eculizumab therapy may show raised C5 antigen levels. This occurs because the test cannot distinguish between free C5 and C5 bound to the drug. In such cases, a functional test provides a clearer assessment of active C5 activity.
How to Maintain Healthy Levels
General immune health supports the complement system. The following steps may help maintain healthy immune function:
- Eat a balanced diet rich in protein, vitamins, and minerals that support immune function.
- Work with your doctor to manage chronic conditions such as autoimmune diseases that may affect complement activity.
- Discuss meningococcal vaccination with your doctor if a complement deficiency is diagnosed, as vaccination is important for prevention in such cases.
Lupin Diagnostics C5 Complement Test Price and Home Collection
C5 Complement Test (Functional Assay)
The C5 Complement test is a specialised immunology test with an approximate price of ₹6,400, based on aggregator sources. Home sample collection is available, making it convenient to complete the test without visiting a diagnostic centre.
Price by City
| City | Approximate Price (₹) |
|---|---|
| Mumbai | ₹6,400 |
| Pune | ₹6,400 |
| Hyderabad | ₹6,400 |
| Bengaluru | ₹6,400 |
| Kolkata | ₹6,400 |
Prices are indicative and may vary by location. Please confirm the current price at the time of booking.
How to Book
- Select the test on the Lupin Diagnostics website.
- Choose your city and preferred time slot.
- Opt for home sample collection by a certified phlebotomist, or visit your nearest Lupin Diagnostics centre.
- Receive your report via email or WhatsApp within the stipulated turnaround time.
Home Collection
Lupin Diagnostics offers home sample collection for the C5 Complement Functional Assay across multiple cities in India. All samples are processed in NABL-accredited laboratories by experienced staff. Digital reports are delivered directly to your email or WhatsApp so doctors can review them promptly.
Frequently Asked Questions
The antigen test measures how much C5 protein is present in the blood. The functional test checks whether that protein is actually working as it should. In rare cases, a person may have normal C5 levels, but the protein is inactive, so a functional test is needed to detect the deficiency.
The CH50 is a screening test for overall complement function. A deficiency in any single complement component, including C5, will result in an undetectable CH50 result. Doctors typically use CH50 as a first step and then order the C5 Complement test to identify which specific component is deficient.
People with C5 deficiency cannot properly form the membrane attack complex, which is needed to fight certain bacteria. This makes them more susceptible to Neisseria infections, including Neisseria meningitidis and Neisseria gonorrhoeae.
Yes. If you are taking eculizumab or another C5 inhibitor drug, your C5 antigen levels may appear elevated. This is because the test cannot separate drug-bound C5 from free C5. Always tell your doctor and the laboratory about any medications you are currently taking.
Yes, C5 deficiency is a rare genetic condition. It follows an autosomal recessive pattern, meaning a child must inherit a faulty gene from both parents to develop the condition. It results in insufficient or non-functional production of the C5 protein.
After the blood draw, the sample must be allowed to clot, and the serum must be separated within two hours. It should then be frozen immediately. Correct cold-chain handling is essential for this test, as improper storage is a leading cause of inaccurate results. The Lupin Diagnostics home collection team is trained to manage this correctly.
Results are typically available within 2 to 6 days. You will receive your digital report via email or WhatsApp once it is ready.
C5 Complement Test: Booking, Price, and Results
